Adds torch.compile support for torch>=2.4.0 by refactoring the ops/functions python interface and optionally registering libnatten ops with torch.library instead of creating autograd ops.

More information on why all of these steps are necessary:
https://pytorch.org/tutorials/advanced/python_custom_ops.html

Fixes #89 .

TODOs:

• verify torch.compile works without graph breaks
• make registering with torch.library optional (forward mode AD still doesn't have an interface)
• torch.compile unit tests
• verify mixed precision still works with torch.library
• verify training NAT/DiNAT with torch.compile is functional